<!doctype html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>浮动</title>
	<style type="text/css">
		div{
			width: 200px;
			height: 200px;
			background: red;
			font-size: 50px;
			color: #ffffff;
			
		}
		.box1{
			background: red;
			float: left;
			
		}
		.box2{
			background: blue;
			float: left;
		}
		.box3{
			background: yellow;
			float: left;
		}
		.box4{
			background: green;
			float: left;
		}
		.box5{
			width: 700px;
		}
		.box6{
			height: 220px;
		}
	</style>
</head>
<body>
	<div class="box1">1</div>
	<div class="box2">2</div>
	<div class="box3">3</div>
	<div class="box4">4</div>
	<div class="box1">1</div>
	<div class="box2 box6">2</div>
	<div class="box3">3</div>
	<div class="box4 box5">4</div>
</body>
</html>